My Lovable App Is Broken — How to Fix It (2026 Guide)

Lovable is one of the fastest ways to build a web app in 2026. You describe what you want, the AI builds it, and within hours you have something that looks and works like a real product. Until something breaks.

The most common experience: you get 80% of the way there, something stops working, and no matter what you tell the AI, it either makes it worse or goes in circles. This guide covers the most common Lovable app failures and how to fix them — either yourself or by knowing exactly what to ask a developer.

Problem 1: Blank White Screen After Deploy

This is the most common Lovable issue. The app works in the Lovable preview but shows a blank page when you share the link or deploy to your custom domain. The cause is almost always a routing issue — the app uses React Router or similar, and the server is not configured to handle client-side routes.

Fix: If you are deploying to Netlify or Vercel, add a _redirects file (Netlify) or vercel.json with rewrites that point all routes to index.html. If you are on a custom server, configure the web server to serve index.html for all paths. This is a one-time server configuration fix, not a code issue.

Problem 2: Supabase Connection Errors

Errors like 'Failed to fetch', '401 Unauthorized', or 'relation does not exist' usually mean one of three things: your Supabase URL or anon key is wrong, your Row Level Security (RLS) policies are blocking the request, or the table the code expects does not exist in your database.

Fix: Check your Lovable environment variables — VITE_SUPABASE_URL and VITE_SUPABASE_ANON_KEY must match exactly what is in Supabase → Project Settings → API. For RLS errors, go to Supabase → Table Editor → your table → RLS policies and add a policy that allows the operation your app is trying to perform.

Problem 3: Auth Not Working / Users Cannot Log In

Common causes: the auth provider is not enabled in Supabase, the redirect URL is not in the allowed list, or email confirmation is required but your app is not handling the confirmation flow. Fix: Supabase Dashboard → Authentication → Providers → enable the providers your app uses. Under URL Configuration, add your app URL to the allowed redirect URLs list.

Problem 4: AI Keeps Making the Same Part Worse

You ask Lovable to fix a bug, it changes something, creates a new bug, you ask it to fix that, it breaks something else. This loop is a sign the AI has lost context of your app architecture. Fix: Start a new Lovable conversation and describe the exact current state — what the app should do, what it is actually doing, and what error appears in the browser console (F12 → Console). Specific error messages get specific fixes. 'It does not work' gets guesses.

Problem 5: App Works in Preview But Not on Your Domain

Environment variables are the usual culprit. In Lovable's preview, your Supabase keys are set. When you deploy elsewhere, those variables are not automatically carried over. Check your deployment platform's environment variable settings and ensure all VITE_ prefixed variables are configured.

When to Get a Developer Involved

If you have been going back and forth with Lovable for more than 2 hours on the same issue, the problem is likely architectural — something the AI built incorrectly from the start that now needs a proper fix. A developer who works with Lovable-exported code can typically resolve these issues in 2 to 4 hours. At Saurabh Infosys, we fix Lovable apps — share your repo and we will diagnose it within 24 hours.